Charles e



(No Model.)

0. E. HART.

DRIVE GHAIN.

No. 476,637. Patented June 7, 1892.

lhvtTnn STATns PATENT Trice.

CHARLES E. HART, OF NEW' BRITAIN, CONNECTICUT, ASSIGNOR TO THE STANLEY WORKS, OF SAME PLACE.

DRIVE=CHA!N.

SPECIFICATION forming part of Letters Patent No. 476,637, dated June 7, 1892.

Original application filed November 11, 1891, Serial No, 412,410. Divided and this application filed April 30, 1892. Serial No. 431,247. (No model.)

To a, whom it may concern:

Be it known that I, CHARLES E. HART, a citizen of the United States, residing at New Britain, county of Hartford, and State of Connecticut, have invented certain new and useful Improvements in Drive-Chains, of which the following is a specification.

My invention relates to improvements in drive-chains; and the object of my improvement is to form the knuckle portion of two thicknesses of metal fastened together to prevent the outer thickness from slipping upon the inner one under a pulling strain.

In the accompanying drawings, Figure l is a plan view of two links of my drive-chain. Fig. 2 is a central longitudinal section of one of said links. Fig. 3 is a like section of the knuckle portion of a similar link, but with a different locking device at said line of section, and Fig. a is a plan of the blank from which the links in Figs. 1 and 2 were formed.

I prefer to form my link from a compound blank like Fig. 4, the same consisting, substantially, of two link-blanks, united at their pintle-forming ends, as shown, and I double said blank upon itself at the middle portion, which forms the pintle portion 5 of the complete link. The tongue 6, which is to form the inner thickness of the knuckle portion '7, is made shorter than the tongue 8, which is to form the outer thickness of said knuckle portion. I also make the opening 9 at the end of the compound blank having the short tongue 6 a little longer than the opening 10 at the opposite end. These long and short tongues in the blank are rolled or coiled into the knuckle portion 7. I prefer to form a notch ll, Fig. 4, in the blank for the inner thickness, and when the knuckle portion is rolled, or at a subsequent operation, I swage or bend the outer end of the outer thickness abruptly to the curve of said knuckle into said notch, as at 12, whereby it is seated on the outer end surface of the inner thickness to form a lock and fasten said two thicknesses together at a point within the curve of said knuckle portion to prevent them from slipping one upon the other, with a tendency to straighten out under a pulling strain, as they would do were they not so fastened or locked.

As a substitute for the look at 12, or as an additional lock 1 may use a pin or pins extending through both thicknesses of metal at any desired point or points within the curved portion of the pint-leas, for instance, the pins 13 in the curved part of the knuckle portion that leads from the ends of the side bars 14 or the pin 15 at a point nearer the outer end of the knuckle portion. \Vhen the look at 12 is omitted, it is only necessary to dispense with the operation of swaging or bending the outer end of the outer thickness over the end of the inner one, whether the notch 11 is present or not; but of course this notch may be omitted, leaving the end of the tongue 6 in the blank square across, thereby forming the outer end of the knuckle portion, as shown in Fig. 3.

I have shown the lips 16 as swaged up between the side bars, but I do not herein claim the same, as they are made the subject of my application, Serial No. 412,410, filed November 11, 1891, of which this application is adivision. It is evident that the presence or absence of these lips are immaterial to my looking device, and while I have described a complete link and one way of making the same, it is evident that the essential feature thereof, so far as this division of my application is concerned, is a link having a knuckle portion consisting of two thickneses of metal, coiled one over the other and fastened together by a locking device, the advantages of which remain the same, no matter what the construc tion of the other parts of the link may be.

I claim as my invention In a drive-chain, a link having a knuckle portion formed of two thicknesses of metal rolled or coiled one around the other, said two thicknesses being fastened together by a locking device within the rolled or curved part of said knuckle portion, to prevent the outer thickness or coil from slipping upon the inner one under a pulling strain, as specified.

CHARLES E. HART.

itnesses:

JAMES SHEPARD, BRAYTON S. LEWIS. 

